1. Field of the Invention
The invention relates generally to the art of refrigeration. In refrigeration compressors, particularly of the helical screw type, oil is required to seal, cool, lubricate and to actuate moving parts. Resultantly, oil becomes mixed with the high pressure refrigerant and must be removed continuously. Oil separators are generally positioned in such systems at the discharge of the compressor and ahead of the condenser.
2. Description of the Prior Art
As indicated above, the need for oil separators has been present for many years and various types have been employed.
Examples of separators in prior United States patents are noted as follows.
The Wheeler U.S. Pat. No. 441,995, discloses an oil separator having a tangential inlet flow along a spiral passageway so that the oil tends to flow downwardly along the outer sides of the passageway, and the vapor is withdrawn upwardly through the central portion of the passageway.
The Forster U.S. Pat. No. 1,982,733 discloses an air and dust separator in which the air-dust mixture tangentially enters the elongated casing at the top, through an expanded inlet pipe, thereby reducing its inlet velocity. It enters above the level of the rotary vanes and thus must turn downwardly before engaging the vanes, the air thereafter turning upwardly to escape through the sleeve. The lower portion of the casing tapers to reduced diameter for maintaining the whirling of the dust and its descent to the outlet.
The Ammons U.S. Pat. No. 2,692,027 discloses a tangential inlet with a cylindrical screen at the lower portion of the housing through which the vapor passes prior to being drawn upwardly through an outlet.
The Ramsey U.S. Pat. No. 3,304,697 discloses a tangential inlet into a vessel with an inner chamber, the vapor being drawn upwardly through a central outlet.
The Paugh U.S. Pat. No. 3,499,270 discloses a tangential inlet with a tapered inlet tube into a conical chamber so that the oil is deposited around the sides of the chamber and the vapor is deflected upwardly from a central plate through an outlet stack into a filter assembly forming a secondary separator.
The Uratani U.S. Pat. No. 3,520,149 discloses a tangential inlet around a centrally located housing which holds a filter material through which the gas flows upwardly.
The patent to Quick discloses a tangential inlet for a separator in which the gas flows upwardly through a cylindrical filter at the upper portion and then is discharged downwardly through an outlet pipe.
The Lawser U.S. Pat. No. 3,778,984 discloses a tangential inlet and the gas discharging through a cylindrical screen to an outlet in the upper central portion of the vessel.
The Goransson et al. U.S. Pat. No. 4,113,450 discloses a tangential inlet and a cylindrical filter in the upper portion of the vessel through which the vapor passes.
The Laval U.S. Pat. No. 4,305,825 discloses a tangential inlet into a vessel having an impingement disk in the lower portion against which the vapor carrying oil impinges, the oil then draining downwardly from the disk and the vapor being deflected upwardly through a central outlet member.
The DiCarlo et al. U.S. Pat. No. 4,506,523 discloses a tangential inlet into a vessel having screen along the sides and an upper central outlet.